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A Blasetti

Publications and source records attributed to A Blasetti.

At least 19 recordsLinked to original sources
PubMed2006

Positional cloning of a cyromazine resistance gene in Drosophila melanogaster.

Cyromazine is an effective insecticide used to control dipteran insects. Its precise mode of action is yet to be determined, although it has been suggested that it interferes with the hormone system, sclerotization of the cuticle, or nucleic acid metabolism. To understand the way in which cyromazine acts, we have positionally cloned a cyromazine resistance gene from Drosophila melanogaster. Six cyromazine resistance alleles had previously been generated by ethyl methanasulphonate treatment. Two of these failed to complement each other and here we identify them as having independent non-sense mutations in CG32743, which is an ortholog of Smg1 of worms and mammals and encodes a phosphatidylinositol kinase-like kinase (PIKK). RNAi experiments confirm that cyromazine resistance can be achieved by knocking down CG32743. These are the first cyromazine resistant mutations identified at the nucleotide level. In mammals Smg1 phosphorylates P53 in response to DNA damage. This finding supports the hypothesis that cyromazine interferes with nucleic acid metabolism.

Alleles↗
PubMed2005

HLA DR/DQ alleles and risk of type I diabetes in childhood: a population-based case-control study.

The objective was to evaluate HLA DR/DQ alleles and their risk factor for type 1 diabetes in the Abruzzo region (central Italy). Sixty incident cases from the Abruzzo region were studied together with 120 unrelated control subjects living in the same administrative areas. The relative risk of diabetes associated with the alleles under study was calculated by deriving the odds ratio (OR) maximum likelihood estimates and their 95% confidence intervals (CI) by the exponentiation of the logistic regression beta-parameter. The combination DRB1*03/DQA1*0501/DQB1*0201 was found in 20.0% of patients and 7.1% of the control subjects, conferring an OR of 4.04 and a CI of 1.97-8.49. The combination DRB1*04/DQA1*0301/DQB1*0302 was found in 23.3% of diabetic patients and 6.7% of controls, giving an OR of 5.69 and a CI of 2.77-12.05. DRB1*11/DQA1*0505/DQB1*0301 and DQA1*0505/DQB1*0301 were negatively associated with type 1 diabetes (OR=0.27, CI 0.11-0.57; OR=0.07, CI 0.02-0.19). The DQA1 genotype at risk was found to be DQA1*0301/DQA1*0501: OR=23.80, CI 2.97-190.89, as it occurred with the highest frequency in the patient group. The DQB1 genotype at risk was found to be DQB1*0201/DQB1*0302, which occurred in 13.3% of patients but in only 1.1% of the control group (OR=29.75, CI 5.36-549.25). Our results shed further light on the risk of development of this disease during a specific time period in an area where the overall incidence of type 1 diabetes is known.

Alleles↗
PubMed2005

Recent advances on autosomal dominant nocturnal frontal lobe epilepsy: "understanding the nicotinic acetylcholine receptor (nAChR)".

Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is characterized by clusters of nocturnal motor seizures, which are often stereotyped and brief. They vary from simple arousals during sleep to dramatic, bizarre, hyperkinetic events with tonic or dystonic features. A minority of patients may experience aura. This disease is caused by various mutations of genes coding for subunits of neuronal acetylcholine receptor comprising the sodium/potassium ion channel. Recent advances in molecular genetics have provided the means for a better understanding of human epileptogenesis at a molecular level, which can facilitate clinical diagnosis and provides a more rational basis of therapy of this form of epilepsy. In this review, we report the recent data in the genetics of ADNFLE.

Epilepsy, Frontal Lobe↗
PubMed2001

Paroxysmal tonic upgaze of childhood: effect of age-of-onset on prognosis.

UNLABELLED: Paroxysmal tonic upgaze (PTU) is a syndrome of childhood manifesting as sudden ocular movements with sustained upward deviation of the eyes. We describe the outcome of 6 patients, after a follow-up of 10 years, with onset of the disease in childhood. The aims of this study were to clarify some clinical features of this syndrome and to evaluate the long-term prognosis of these children. In all the patients, tonic upgaze episodes disappeared with time to remission, varying from 1 to 4 y, without any therapy and without any change in psychomotor development, EEG and neuroimaging. Only one child had pathologic interictal EEG with temporo-occipital spikes, which persisted after the offset of the disease. CONCLUSION: From a long-term follow-up, we can confirm the good prognosis of PTU and suggest it is possible to define a distinct syndrome of childhood without any neurological abnormalities and with spontaneous resolution.

Age of Onset↗
PubMed1998

Size of pancreas in children and adolescents with type I (insulin-dependent) diabetes.

PURPOSE: The aim of this study was to evaluate the influence of insulin-dependent diabetes mellitus (IDDM) on the size of the pancreas in children. METHODS: Pancreas size was evaluated sonographically in a group of 60 diabetic children and adolescents, aged 3-15 years, and 60 sex- and age-matched healthy controls. RESULTS: A significant reduction in pancreatic area and other parameters was found in diabetic patients particularly in children aged 8-12 and 13-15 years. The pancreas was larger in children 3-7 years old who had had IDDM for 2 years of less (mean size, 8.61 cm2) than in children 8-12 and 13-15 years old who had had IDDM for more than 5 years (mean size, 8.06 and 8.40 cm2, respectively). An inverse correlation between area of the pancreas and duration of IDDM was seen in all age groups (p < 0.05). CONCLUSIONS: Diabetes affects the growth of the pancreas in children with IDDM. Sonography can be used to noninvasively evaluate the influence of the disease on pancreas size.

Adolescent↗
PubMed1998

Family history and risk of insulin-dependent diabetes mellitus: a population-based case-control study.

Insulin-dependent diabetes mellitus (type 1) is a common chronic disease of childhood occurring throughout the world. In the literature, its most important determinants include genetic, environmental and familial factors. We evaluated family history as a determinant of the risk of type 1 diabetes mellitus with a population-based case-control study. Information about type 1 patients was taken from the dedicated register of the Abruzzo Region; the register has been collecting incident cases in the age group 0-14 years, diagnosed between 1 January 1990 and 31 December 1996. The control group was taken from the lists of patients attending family pediatricians. The family history data for type 1 and type 2 patients was obtained by a questionnaire, administered to their parents. The risk of type 1 diabetes mellitus associated with its occurrence in first- and second-degree relatives was estimated using logistic regression methods. Our results show that the risk is indeed increased with a positive family history (OR=3.96; 95% CI 1.54-10.14). This shows that the risk of type 1 diabetes mellitus for children whose fathers are affected by the disease is 11 times higher with respect to controls. Moreover, the risk for children whose brothers are affected by the disease is 20 times higher with respect to controls. In contrast, a family history for type 2 diabetes mellitus does not influence the risk.

Adolescent↗
PubMed1996

Severe hypoglycemia in insulin-dependent diabetic children treated by multiple injection insulin regimen.

The occurrence and risk factors of severe hypoglycemic attacks were analyzed during a 4-year study in a group of children and adolescents who received human insulin and followed a multiple daily injection regimen (three or four injections per day); 29 patients experienced severe hypoglycemia at least once in 4 years. Of these, 13 suffered recurrent episodes: 8 had two episodes, 4 had four episodes, and 1 patient had seven episodes. For comparative purposes, the nonhypoglycemic population (217 diabetic children) was used as a control group. The hypoglycemic children received insulin doses which were significantly higher than for nonhypoglycemic patients (1.05 +/- 0.6 U/kg daily vs 0.87 +/- 0.7; P < 0.05). Moreover, the hypoglycemic group had a significantly higher mean number of previous episodes of severe hypoglycemia than the nonhypoglycemic group (0.98 +/- 1.2 vs 0.26 +/- 0.7; P < 0.001). There was no significant difference in age, sex, duration of disease, and metabolic control between hypoglycemic and nonhypoglycemic children. There was no association between severe hypoglycemia and the presence of retinopathy, persistent microalbuminuria, or autonomic neuropathy. Severe hypoglycemia is a recurrent problem, not related to the quality of metabolic control nor to the presence of long-term microvascular complications, and diabetic children with a personal history of severe hypoglycemia are at risk for future episodes.

Adolescent↗
PubMed1995

Autonomic neuropathy in diabetic children.

OBJECTIVE: Evaluate the presence of cardiovascular autonomic nerve dysfunction in children and adolescents with insulin-dependent diabetes mellitus. METHODOLOGY: We studied 110 patients (54 male, 56 female) and 100 healthy sex and age-matched children. Autonomic nerve function was assessed by standard cardiovascular reflex tests: (1) Fall in systolic blood pressure in response to standing. (2) Heart rate in response to standing. (3) Beat-to-beat rate variation during deep breathing. (4) Quotient of heart rate during and after Valsalva manoeuvre. (5) Change in blood pressure response to sustained handgrip. The coefficient of variation of heart rate was determined from 150 systoles using a microcomputer-based technique. The lower limits of normal were defined according to statistical analysis taking into account the relationship between heart rate variability and age. RESULTS: Forty-seven of the 110 diabetic children and adolescents studied showed one or more abnormal tests for cardiovascular autonomic dysfunction; many patients had an abnormality in more than one test. Twenty-two patients showed early involvement, 18 patients had definite and 7 severe involvement. No correlation was found between sex, glycaemic control, duration of diabetes or presence of retinopathy and persistent microalbuminuria and the autonomic nerve function. CONCLUSIONS: In the paediatric age group also, autonomic nerve dysfunction can be present in asymptomatic diabetic patients. Heart rate variation during Valsalva manoeuvre and maximum/minimum 30:15 ratio are the most sensitive indices to detect autonomic abnormalities in children.

Adolescent↗
PubMed1992

[Immunologic changes in diabetic ketoacidosis].

We studied 13 children and adolescents during diabetic ketoacidosis; the duration of diabetes ranged from 1.4 to 6.0 years. A group of 13 diabetic sex, age and duration of disease-matched children served as control. Patients in ketoacidosis showed important abnormalities of T subset percentages (OKT3: 63.4 +/- 1.87% vs 72.1 +/- 3.4; p less than 0.001. OKT4: 37.18 +/- 1.85% vs 44.6 +/- 3.9; p less than 0.01. OKT8: 28.5 +/- 6.51% vs 28.1 +/- 1.9; p less than 0.04) and impaired neutrophil chemotaxis (53.10 +/- 3.3 vs 88.1 +/- 7.2; p less than 0.001). The patients showed normal levels of all classes of immunoglobulins. No correlation was observed between these abnormalities and the degree of ketoacidosis or glycaemia. When the patients were re-evaluated out of ketoacidosis, the values of the immunological parameters were normal and similar to those of the control group.

Chemotaxis, Leukocyte↗
PubMed1990

[Myelodysplastic syndrome: experience of the Study and Treatment of Bone Marrow Failure Group].

Myelodysplastic syndromes (SMD) were studied in 58 patients (37 men, 21 women; mean age 61 years, range 18-81) who were grouped according to FAB criteria (Table 1). None of them showed a secondary SMD to medullary toxic agents or cytostatic treatments although 5 presented concomitant neoplastic disease. Morphologic alterations in peripheral blood smears and bone marrow were registered by 3 hematologists working independently. The intracellular and extracellular iron deposits were evaluated in every case with Perls; peroxidase activity was determined in 16 patients and intraleucocitary alkaline phosphatase reaction was carried out in 17 patients. Twenty five patients (43%) had refractory anemia (RA); 10 (17%) sideroblastic anemia; 13 (25%) refractory anemia with excess of blasts (AREB); 3 (5%) AREB in transformation (AREB-T) and 7 myelomonocytic leukemia (LMMC). Clinical manifestations at diagnosis are described in Table 2. In the observation period there were cases of anemia requiring transfusion, bacterial infections, muco-cutaneous hemorrhage and hemorrhagic episodes in the central nervous system. In the bone marrow smears the cellularity was normal or increased in 53 cases and diminished in only 3. The degree of dysplastic characteristics (erythroid, granulocytic and megakaryocytic) ranged from low to severe. It was low in most of AR, being the erythroid population the most affected in AS and the granulocytic one in AREB and AREB-T. Patients with LMMC showed similar characteristics to those with myeloproliferative syndromes and the differential diagnosis were sometimes difficult, accounting for their separate inclusion in Table 4. Out of 23 patients, 5 presented clonal pathology detected in cytogenetic studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Long-term study on T lymphocyte subsets in newly diagnosed type 1 diabetes mellitus.

T lymphocyte subsets in peripheral blood from 16 newly diagnosed type 1 diabetic children were studied prospectively at four time intervals: as soon as possible after diagnosis and 1, 4 and 12 months later. T lymphocyte subsets were analysed using monoclonal antibodies and counted by cytofluorimetry. The percentage of T lymphocytes (OKT3+ cells) did not change at the four study times. The percentage of helper/inducer T cells (OKT4+ cells) was high at the diagnosis (43.1 +/- 2.1%), but decreased after 1 and 4 months with no difference in the control values. The percentage of suppressor/cytotoxic T lymphocytes (OKT8+ cells) was low at the diagnosis, but increased after 1 and 4 months. The OKT4/OKT8 ratio was 2.31 +/- 0.22 at the diagnosis study, decreasing to 1.83 after 1 month, compared with 16 sex- and age-matched control children. The high percentage of helper/inducer T lymphocytes and low number of suppressor/cytotoxic T cells at onset of diabetes favour immune reactions that lead to beta-cell damage.

Adolescent↗
PubMed1984

In vitro bone marrow GM-CFC growth in aplastic patients. Correlation between E rosette forming cells and immunotherapy results.

In vitro bone marrow GM-CFC (granulomonocyte colony forming cell) growth following E rosette (+) cell depletion was studied in 14 aplastic patients to determine whether an autoimmune factor could be involved in the pathophysiological process leading to the decrease in bone marrow colony formation. The increase in GM-CFC growth after E rosette (+) cell depletion was high in 8 cases, suggesting that in these cases an autoimmune mechanism may have been involved. All these patients responded within a month to treatment with antithymocyte globulin (ATG) or corticosteroids. Six patients did not respond to immunotherapy, none showed increased GM-CFC growth. The increase of in vitro GM-CFC growth after E rosette (+) cell depletion in aplastic anemia could therefore be a good indication for the trial of immunotherapy. However this study seems to be useful only in patients with at least a few months evolution after diagnosis.

Adolescent↗